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1

Sun dogs are bright spots to one or both sides of the sun. They are a form of halo created by ice crystals in the atmosphere. What you saw was most likely cloud iridescence, which is a phenomenon that occurs closed to either the moon of the sun. The iridescence is caused by diffraction created by water droplets or small ice crystals individually scattering ...


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Dust would not have to be chemically poisonous to render air unbreathable but a big impact would first of all release a blast of hot plasma that nothing nearby will survive with accompanying air blast. Dust would be mostly from Earth material and that will vary in chemistry according to what is locally present; the Chicxulub (dinosaur killer) impact hit ...


2

Clouds absorb thermal radiation and re-emit it, so that some of it comes back towards the Earth (Behind the Forecast: How clouds affect temperatures). During the day this warming effect is balanced by the cooling effect of blocking out the sunlight. They don't strictly speaking stop the formation of dew, but they make it less likely. In the words of NASA's ...


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Water vapor is an extremely potent greenhouse gas. But, like all greenhouse gases, water vapor is transparent to some portions of the thermal infrared, and even where absorptivity is relatively high, a thick column of water vapor is needed to absorb almost all of the incoming thermal radiation. Liquid water and ice are much better, and much less selective ...


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There are several reasons. From the theoretical point of view it is beneficial to use isobaric coordinates, due to the vanishing density in the equations of motion. While in cartesian coordinates the wind is determined by the pressure gradient in isobaric coordinates the wind is determined by the geopotential gradient. The geopotential is defined by $\Phi = ...


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Yes. You don't even need concrete or black paint, just a plowed field will do, or grass vs forest, a south facing slope... (Ask anyone who's done much sailplane flying.) How high the convection will reach depends on a lot of factors. Hereabouts (east side of the Sierra Nevada) you can easily thermal to 14,000 ft (~4500 m) or more. (Going higher requires ...


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In principle: yes. But i won't give exact numbers for a mere km², though i'd expect a skilled paraglider under optimal atmopsheric conditions to be able to make some use of it ;-) Actually, gliders use industrialized areas exactly because of this, a low albedo created by asphalt, concrete, dense construction/building. How high and strong the resulting ...


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"Each part per million by volume of $CO_2$ in the atmosphere represents approximately 2.13 gigatonnes of carbon". Per a_donda's comment,"During the carboniferous, atmospheric $CO_2$ sank from ~1500 to ~250ppm", so, about 2.7 trillion tonnes. "There are an estimated 1.1 trillion tonnes of proven coal reserves worldwide." The latter number does not include ...


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